Comtech EF Data DMD-2050E - Manual (Page 102)

DMD2050E Universal Satellite Modem Theory of Operation
MN-DMD2050E Revision 2 3–60
Kbps
Standard IBS
Baud Rate Example
Kbps
Enhanced Mode
Baud Rate Example
896 19200
960 19200
1024 19200
1088 19200
1152 19200
1216 19200
1280 19200
1344 19200
1408 19200
1472 19200
1536 19200
1600 19200
1664 19200
1728 19200
1792 19200
1856 19200
1920 19200
1984 19200
2048 19200
3.16 Standard IBS Mode
In the first or “Normal” mode, all bit assignments are per the IBS standard. The bits of Overhead
Housekeeping byte 32 are implemented as shown in Table 3-6.
Table 3-6. Bits of Overhead Housekeeping Byte 32
Bit 1 ES to ES Data Channel This bit is routed directly to the ES to ES Data Channel. Its data rate is 1/512th
of the aggregate rate (or 1/480th of the through terrestrial data rate), and is
normally used to super-sample an asynchronous data channel.
Bit 2 Frame Alignment Part of the Frame Alignment word.
Bit 3 Backward Alarm Transmit and Receive with main processor to activate Main Alarm/LED.
Bit 4 Multiframe Message As per IBS.
Bits 5
and 6 Spare Not currently utilized.
Bits 7
and 8 Encryption Utilization Not currently utilized.